Trailer Tire Size for Sportboat Trailers

[rkgallagher]

We have a tandem Sportboat Trailer for a 2002 Response LX. Currently, there are Kumho tires on it. The tire size is 195/R65/15. We'd like to go with a Goodyear Marathon, but they don't make that tire in this size. What tire size do you recommend? What are the options? Is load D worth spending more money on?

[NorCaliBu]

Gee Whiz! Ryan's back. Where you been hiding? Wish I had some advice for you on the tires. Doesn't look like much is available in the Goodyear Marathon in 15".

[rkgallagher]

Yes, I'm back. It's been too long. I wish I could say I was out skiing. Maybe I'll try calling SportBoat Trailer Co. and see what they recommend.

[DONTW8]

Go to Tire Rack and weigh your options.

The Kumho tire I find in a size of 195/65r15 is a passenger car tire, 7.9" wide x 25" diameter, has a load rating of 1356 pounds in their Ecsta series.

For trailer tires I will only use a "C" (6 ply substitute) or "D" (8 ply substitute) in trailer service tires. This has been discussed at length on this forum.

I recently raised my trailer fenders to allow a larger trailer service tire underneath.

If you can the optimum would be 225/75r15 "D" rated tires with a 2540# rating per tire. 8.8" width x 28.3" height cost of $91.

Next choice 205/75r15 "C" rated with an 1820# rating, 8" wide x 27.1 diameter, cost of $79.

Get out your tape rule. Your limiting factor may be the length distance between your fender brackets and the spacing between your axles.

My experience is no flats or blowouts in 37 years of owning trailer boats. It's the load (ply) rating and maximum allowed tire pressure that does it. Heat is the enemy and with the full 50# psi "C" or 65# psi "D" you remove the heat buildup from flex.

Edited September 6, 2009 by DONTW8

[DONTW8]

One other consideration:

Tire Rack has a Kumho trailer service tire in load range "D" that may fit your trailer. You would have to buy 14" wheels but you gain capacity.

Kumho 205R14 "D" load rated , capacity 2271 # at 65 psi.

27" diameter and 8.2" section width.

Where your current tires are 12.5" radius and these 14" Kumhos have a radius of 13.5" radius they may fit within your current fenders.

Make sure you have clearance for your brake calipers or drums.

http://www.tirerack.com/tires/Spec.jsp?mak...tirePageLocQty=

[rkgallagher]

Thanks for all of the suggestions. I appreciate it.